Brazilian home-electronics retailer Lojas Paraiso SA has filed for protection from its creditors, the second such company to seek credit protection this year and a sign that Brazil's drastic interest-rate tightening is taking its toll on credit-sensitive industries.

The move raised concerns about the fate of other large Brazilian retailers, which tend to sell much of their goods on credit, and hence face defaults by customers when interest rates soar. For instance, shares of electronics retailer Lojas Arapau SA have...